Arch bridge



(No Model.)

J. GOWDON.

ARCH BRIDGE.

No. 414,859. Patented Now-12, 1889,

q vih mowo R W Mm $313 1L4, ("1410114241 f UNITED STATES PATENT OFFICE.

JOHN CONVDON, OF NEIV ORLEANS, LOUISIANA.

ARCH BRIDGE.

SPECIFICATION forming part of Letters Patent No. 414,859, dated November 12, 1889. I

Application filed December 13, 1888. Serial No. 293,513. (No model.)

To all whom it may concern.-

Be it known. that 1, JOHN OOWDON, a citizen of the United States, and a resident of New Orleans, parish of Orleans, State of Louisiana, have invented new and useful Improvements in Arch Bridges, of which the following is a full and exact description, reference being had to the accompanying drawings, making part of this specification.

This invention relates to certain improvements in the construction of arch bridges; and it consists in the peculiar formation of the. tube-sections, the manner in which the same are joined together to form arches for the support of the road-bed, and in the mode of securingthe end sections of the tubes in the piers or abutments.

It also consists in certain details of construction, all of which are hereinafter fully described and specifically claimed.

In the accompanying drawings, Figure 1 is aside elevation of my improved bridge. Fig.

the thrust of same.

2 is an end view of same. Fig. 3 is an enlarged View of the pier or abutment, with end sections of tubes and plates for receiving Fig. 4 is a detailed View of pipe-sections, with suspension-rods, girders, and floor-covering. Fig. 5 is a perspective of a tube-plate before being bent into cylindrical form; and Fig. 6 is a sectional view of a series of pipe-sections joined and secured together by means of rivets, as in the nature of the invention.

The letter A designates abutments or piers, which are built of concrete, with metal plates B embedded therein. The plates B are preferably made with perpendicular backs a, horizontal base I), and inclined face 0, the latter provided with an. annular recess d, of sufli cient diameter to receive the inner end of a tube or pipe section 0, which is held in place by the concrete, and a metal washer D, set in the face of the abutment or pier, and against which the flange or enlarged portion of the aforesaid tube or pipe section 0 is adapted to rest. Thus the plates B and washers D receive the thrust of the tubes and preserve the face as well as the interior of the concrete free from injury, thus-dividing the pressure- The tube or pipe sections 0 are made of steel or other suitable material rolled-in the form shown in Fig. 5, with an offset d, and with rivet-perforations 6 near the outer edges 'of its opposite sides to permit the said sides being secured together after the sections have beenbent into cylindrical form and the'perforated edges thereof made to overlap each other. The opposite ends of each pipe-section are provided with rivet-holes,\as shown at f, to permit the connection of a numberof sections to form a complete arch, as shown in Fig. 1, in which it will be seen that the pipesections abut directly against each other, forming, as it were, a continuous pipe to each arch, and thus relieving the rivets of all strain.

In the erect-ion of each tubular arch the pipe-sections may be lowered into position from one or more wire ropes previously stretched above the piers or abutments, the work beginning at the abutments and continued outward until the crown or key sec-. tion is secured in position; but preferably in the construction of my improved bridge I employ four arched tubes, as shown in Fig. 2,

the inner tubes being about twenty feet apart and the outer tubes being about ten feet to the outer side of same. In the erection of these tubes I propose to employ two flotillas, each composed of a like number of boats strongly braced together and anchored or otherwise secured to the opposite sides of the stream or body of water to be\bridged. The flotillas are arranged on upstream side, with their lower boats near the abutments or piers to be bridged. Above each fiotillaI construct a half-center or scaifold, and on same connect the pipe-sections until one-half of each arch is completed. The upper ends of the flotilla are then allowed to swing outward until they meet, when they are lashed together and the whole fleet slowly drifted downstream and anchored or otherwise secured between the piers or abutments. The arches are then completed by first securing their lower ends to the pipe-sections, which are embedded in the pier or abutments, after which the key or crown sections are secured in their respective places, thus completing each tubular arch. Braces 9 hi are next secured in diagonal positionsbetween the several arches,

spaces being left at each end of the same for the passage of wagons and railroad-trains, as in all other bridges.

At distances of about eight or ten feet apart a the center of the bridge than at the ends thereof. The suspension rods or chains m are made in two sections, and are provided at their adjacent ends with screw-threads to engage like threads in the opposite ends of a swivel E, whereby the tension on each chain or rod is regulated as may be required.

In bridging of streams or bodies of water the plates D, which receive the thrust of the bridge-arches, are, when circumstances will permit, laidin the concrete of which the pier or abutment is composed, at or about on a level with the surface of the soil at the rear thereof, in order that the same may form a backing which will assist in relieving the said pier or abutment of the pressure which is naturally brought to bear thereupon.

Although described as being adapted for spanning water-courses, lakes, or bays, it is evident that my improved bridge maybe used to advantage in spanning ravines or gulleys in mountainous countries, the adjacent sides of the mountains in said cases receiving the thrust of the bridge-arches.

In all cases guys should be stretched at each side of the bridge in order to prevent any lateral motion of same. I

From the above description it will be seen that the most important feature of myinvention consists in the manner in which the tubes or arches are constructed, the sections of which are made to abut squarely against each other, thus relieving the rivets of all strain and making each arch or tube, no matter how long, as solid and strong as though it were one continuous tube or sheet of metal forming the tubes.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. The herein-described tubular arch-supports for bridges, the same .consisting of a series of tube joints or sections adapted to abut squarely against each other, their rolled flanged ends and the opposite ends of each sheet or tube-section being firmly and permanently fastened together with rivets, substantially as described.

2. In combination with the piers or abutments of bridges, the plates B, provided with the annular recess for the reception of the tube-section C, and the washer D, adapted to fit in rear of the collar at the outer end of the tube 0, substantially as set forth.

In testimony whereof I affix my signature 65 in the presence of two witnesses.

JOHN COWDON. Witnesses:

ALEX. Monun, WARREN C. STONE. 

